Divider Parts List

 

Most parts are easily available and non critical – in most cases value can be substituted for something close to hand.

 

LCD is available from ebay, or can be purchased via Farnell (or RS Components) for slightly more cost, stick to the aprox  size shown below to make sure the mounting holes match the pcb. Other sizes will work – but you’ll have to handle the mechanics of bolting things together differently.

 

Keypad can be any arrangement of 4x4 buttons. Farnell keypad (also available via RS) is expensive but allows the buttons to have customisable legends).

 

I’ve broken the parts list into 3 parts, Basic, beeper and sense/ack.

Basic parts provide the basic working controller. Beeper and Sense/Ack are optional.

Beeper adds parts required for the key beep feedback.

Sense/Ack provide the parts to allow the controller to communicate with other equipment.

 

Note: If you don’t add the Sense/Ack circuitry connect pin 2 of IC1 to gnd via a 10k resistor.

 

 

Basic:

 

Part Number

Qty

Value

Notes

C1, C2

2

33pF

 

C3, C4

4

100nF

Decoupling – spread liberally.

C5

1

470uF

 

VR1

1

10k Preset

Contrast control

R1, R2, R3, R4

4

10k

Keypad pull downs

IC1

1

18F452

Pre-programmed with firmware.

IC2

1

7805

And small heatsink.

40 pin IC Socket

1

 

For PIC 18F452

Xtal

1

10Mhz

 

Keypad

1

4 x 4 Matrix

Farnell 1171224 (or 16 buttons…)

LCD

1

4line x 20column HD44780 compatible

Available for around £5 on ebay. (Aprox size 97mm x 59mm, view window 76mm x 25mm).

PCB

1

 

Or stripboard construction.

8 Pin SIL socket

1

 

Only if using Farnell keypad.

Connector

1

4 pin 2.54 pitch

Can solder wires instead.

Case

1

 

To suit (case I used is Farnell  775-319)

Power supply

1

8 – 30v

To suit stepper/stepper controller. If using typical 2A stepper then a 24v laptop psu is ideal. If stepper controller has own supply then any small DC wall-wart will do.

 

Beeper

 

LS1

1

Passive sounder

Passive sounder of the type fitted to computer motherboards.

Q3

1

BC337

NPN transistor (500mA IC)

R5

1

4k7

 

D2

1

BYV27

Any fast switch diode

 

Sense/Ack

 

D1

1

BYV27

Any fast switch diode

Q1, Q2

2

BC337

NPN transistor (500mA IC)

R8, R9

2

4k7

 

R6, R7, R10, R11

4

10k

 

Connector

1

5/6 pin 2.54 pitch

Can solder wires instead